Coated lens and method for manufacturing the same

This application is a continuation application of international patent application PCT/EP2023/057082, filed on Mar. 20, 2023 and designating the U.S., which claims priority to international patent application PCT/CN2022/081592, filed on Mar. 18, 2022, both of which are hereby incorporated by reference in their entireties.

The present disclosure relates to a coated lens having a coating based on a stamping and a method for manufacturing a coated lens having a coating based on a stamping.

WO 2020/078964 A1, on which the disclosure is based, discloses an optical article comprising a base lens substrate and an abrasion resistant coating, the abrasion resistant coating forming at least one optical element protruding from one of the surfaces of the abrasion resistant coating. According to paragraph [063] of WO 2020/078964 A1, the abrasion resistant coating may be prepared from compositions comprising at least one alkoxysilane and/or one hydrolysate thereof, obtained by hydrolysis with a hydrochloric acid solution. According to paragraph [064], the abrasion resistant coating may be based on epoxysilane hydrolysates as described in EP 0 614 957 A1, U.S. Pat. Nos. 4,211,823, and 5,015,523. EP 0 614 957 A1 discloses in examples 1 to 4, comparative example 5, and examples 6 to 10, the use of methanol or colloidal silica in methanol, in example 11 additionally the use of toluene, in the respective composition for preparing the abrasion resistant coating. U.S. Pat. No. 4,211,823 discloses in examples 1 to 3, 6, 8 to 11 the use of methanol silica sol, in example 4 the use of an aqueous colloidal silica condensate and ethyl alcohol, in examples 5 and 7 the use of an aqueous colloidal silica condensate and a mixture of isopropanol and n-butanol, in examples 12 and 13 the use of methanol silica sol, diacetonealcohol and n-butylalcohol, in examples 14, 15 and 20 the use of methanol silica sol and diacetonealcohol and benzylalcohol, in examples 16 and 17 the use of methanol silica sol and methanol, in example 18 and 19 the use of methanol silica sol, benzylalcohol and methanol in the respective composition for preparing the abrasion resistant coating. U.S. Pat. No. 5,015,523 discloses the preparation of the silicon hard coating solutions H1 to H5 each containing colloidal silica in isopropanol or methanol and isopropanol, methanol and/or ethanol. Further, according to paragraphs [066] and [067] of WO 2020/078964 A1, the abrasion resistant coating may have a bi-layered structure as disclosed in EP 2 092 377 A1. All examples given in EP 2 092 377 A1 for the compositions of the lower layer and the upper layer of the respective abrasion resistant coating are each containing methanol, deionized water, 1-methoxypropan-2-ol and/or methyl ethyl ketone. According to paragraph [068] of WO 2020/078964 A1 the abrasion resistant coating that may be used in additive manufacturing or inkjet printing is disclosed in U.S. 2007/0238804 A1. According to the examples given U.S. 2007/0238804 A1 the solvents are distilled off before application.

WO 2020/078964 A1 describes several methods for manufacturing the optical article such as molding, additive manufacturing, or thermal embossing. Thermal embossing may be used when an optical article in which the optical elements protrude from a surface facing away from the base lens substrate is to be obtained. The abrasion resistant coating is applied to a surface by, for example, dip coating, UV or thermally cured and then embossed involving pressure and temperature. The optical elements may be regularly distributed along circles centered on the optical center of the refraction area:

EP 3 561 578 A1 discloses in FIGS. 14a and 14b and describes in paragraph [0102] a spectacle lens having a clear zone and cylindrical concentric rings. No dimensions are given for the cylindrical concentric rings. According to paragraph [0161] of EP 3 561 578 A1 every circular zone should have a radius between 2 and 4 mm comprising a geometrical center located at a distance of the optical center of the spectacle lens greater or equal to the radius+5 mm, the ratio between the sum of areas of the parts of cylindrical concentric rings located inside the circular zone and the area of the circular zone is comprised between 20% and 70%.

WO 2019/166659 A1 discloses in FIGS. 11a and 11b and describes on page 20, lines 10 to 12, the same type of a spectacle lens having a clear zone and cylindrical concentric rings as mentioned before with respect to the FIGS. 14a and 14b of EP 3 561 578 A1. Again, WO 2019/66659 A1, does not disclose dimensions for the cylindrical concentric rings. According to page 28, lines 13 to 18, the ratio, defined as in paragraph [0161] of EP 3 561 578 A1, is comprised between 20% and 70%, between 30% and 60%, or between 40% and 50%. Further, WO 2019/166659 A1 discloses in FIG. 1 and describes on page 20, lines 5 to 7, optical elements as micro lenses positioned along a set of five concentric rings. According to page 17, lines 1 to 5, the optical elements have a contour shape being inscribable in a circle having a diameter greater than or equal to 0.8 mm and smaller than or equal to 3.0 mm.

CN 111103701 A discloses in FIG. 3 a spectacle lens with a central optical region. The central optical region is a circular region within a specified radius in the range of 5 mm to 10 mm. Outside of the central optical region, cylindrical microstructures are arranged in a ring-shaped manner. The radial widths of the cylindrical microstructures are specified to be in a range of 0.5 mm to 2 mm. The distance between the cylindrical microstructures of different rings is in the range of 0.5 mm to 3 mm.

It is an object of the present disclosure to provide a spectacle lens comprising a structurable coating composition. The structurable coating composition should be compatible with different optical materials and integrable into a common coating sequence of a spectacle lens. The object was further to provide an efficient method for manufacturing such a spectacle lens.

Exemplary embodiments, which might be realized in an isolated fashion or in any arbitrary combination, are discussed in detail below.

The coated lens according to the disclosure comprises a coating composition, the coating composition comprises a stamping. The coating composition comprises at least one component selected from the group consisting of at least one epoxide component and at least one (meth)acrylate component.

A coated lens is according to ISO 13666:2019(E), section 3.18.1, a lens to which one or more surface layers have been added to alter one or more properties of the lens. A lens or spectacle lens is according to ISO 13666:2019(E), section 3.5.2, an ophthalmic lens worn in front of, but not in contact with, the eyeball.

The coated lens comprises a coating, the coating comprises a stamping, the coating is based on a coating composition comprising at least one component selected from the group consisting of at least one epoxide component and at least one (meth)acrylate component, the stamping is having in a domain of the stamping a surface power which is different to a surface power of a lens surface of the coated lens comprising the coating outside the domain of the stamping.

The lens surface of the coated lens may be either a front surface or a back surface thereof. The surface power is as defined in ISO 13666:2019(E), section 3.10.4. The domain of the stamping is explained below with respect to the surface topography of the stamping.

Typically, the coating composition comprises the at least one epoxide component and the at least one (meth)acrylate component in a weight ratio selected from at least one of the following ranges:

Typically, the coating composition comprises the at least one epoxide component in a total amount within a range selected from at least one of the following ranges:

Typically, the coating composition is having a viscosity within a range selected from at least one of the following ranges:

Coating composition refers to a state before cure. Coating refers to a state after cure.

Before cure, the coating composition is formable or structurable to result in the stamping. Before cure, the coating composition typically is formable or structurable at a given working temperature, for example, at 22° C.±0.5° C. Before cure, the coating composition typically is additionally characterized by at least one of the following features selected from the group consisting of:

The at least one (meth)acrylate component may be selected from the group consisting of pentaerythritol tetraacrylate [CAS No. 4986-89-4], trimethylolpropane triacrylate [CAS No. 15625-89-5], trimethylolpropane trimethacrylate [Cas No. 3290-92-4], dipentaerythritol penta-/hexa-acrylate [CAS No. 60506-81-2], 1,6-hexanedioldiacrylate [CAS No. 13048-33-4], tetramethylolmethane triacrylate, trimethylolpropanetriethylene glycol triacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, urethaneoligomer tetraacrylate, urethane oligomer hexamethacrylate, urethane oligomer hexaacrylate, polyester oligomer hexaacrylate, diethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, bisphenol A dimethacrylate, 2,2-bis(4-methacryloyloxyethoxyphenyl) propane, glycidyl methacrylate, 2,2-bis(4-acryloyloxypolyethylene glycol phenyl)propane, poly(ethylene glycol) methylether methacrylate [CAS No 36915-72-0]. Typically, the at least one (meth)acrylate component is selected from the group consisting of pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, trimethylolpropane triacrylate, dipentaerythritol hexaacrylate and urethaneoligomer tetraacrylate. Further typically, the at least one (meth)acrylate component is selected from the group consisting of pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate and trimethylolpropane triacrylate.

In case the coating composition comprises at least one epoxide component and at least one (meth)acrylate component, the weight ratio between the at least one epoxide component and the at least one (meth)acrylate component typically is in a range of epoxide component/(meth)acrylate component from 0.64 to 4.3, further typically from 0.7 to 4.1, more typically from 0.8 to 4.0 and most typically from 1.0 to 3.0. In case the coating composition comprises at least one epoxide component and at least one (meth)acrylate component in a weight ratio of epoxide component/(meth)acrylate component typically within one of the before mentioned ranges, the at least one epoxide component and the at least one (meth)acrylate component typically is selected from the respective group mentioned before.

In case the coating composition comprises at least one epoxide component and at least one (meth)acrylate component, typically the total amount

In case the coating composition comprises at least one epoxide component, i.e., in case the coating composition comprises the at least one epoxide component only and no additional (meth)acrylate component, the at least one epoxide component typically is based on cationic-polymerizing epoxy resins such as the ones commercially available as DELO KATIOBOND series, company DELO, in particular the pressure sensitive epoxy-based adhesive DELO KATIOBOND PS6372.

In case the coating composition comprises at least one (meth)acrylate component, i.e., in case the coating composition comprises the at least one (meth)acrylate component only and no additional epoxide component, the at least one (meth)acrylate component typically is based on modified acrylates such as the acrylate-based adhesives commercially available as DELO PHOTOBOND series, company DELO, in particular the pressure sensitive acrylate-based adhesive DELO PHOTOBOND PS4130.

Typically the coating composition comprising the at least one epoxide component and the at least one (meth)acrylate component comprises at least one catalyst. The at least one catalyst may be selected from the group consisting of triarylsulfonium salts, preferable triarylsulfonium hexafluorophosphate, 50% in propylene carbonate [CAS No. 109037-77-6, company Sigma Aldrich]; alpha-amino acetophenones, for example 2-methyl-1-[4-phenyl]-2-morpholinopropan-1-one [CAS No. 71868-10-5, Irgacure 907], 2-benzyl-2-dimethyl amino-1-(4-morpholinophenyl)-butanone-1 [CAS No. 119313-12-1, Irgacure 369]; monoacyl and bisacyl phosphine oxides and sulphides, such as phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide [CAS No. 162881-26-7, Irgacure 819].

Typically, the coating composition consisting of the at least one epoxide component, the at least one (meth)acrylate component and the at least one catalyst, each typically being selected from the respective group mentioned before, comprises the at least one catalyst typically in a total amount within a range of from 1% by weight to 4% by weight, further typically from 1.5% by weight to 3.5% by weight, more typically from 1.7% by weight to 3% by weight, and most typically from 2% by weight to 2.7% by weight, each total amount being based on the total weight of the coating composition.

Typically the coating composition is compatible with different optical materials a lens substrate may be based on. Further typically, the coating composition is compatible with common optical material of lens substrates, such as for example, 1.5 CR 39, 1.60 MR-8, 1.67 MR-7, 1.67 MR-10, 1.74 MR-174, 1.53 Trivex.

Typically the coating composition is compatible with various coating compositions applied to the coating composition.

The compatible means the coating composition presents sufficient wettability to the lens substrate to form a coating layer, the coating layer presents sufficient adhesion to the lens substrate, the coating layer does not present defects like bubbles, cracks and pinpoints because of unfavorable chemical reactions between the coating composition and the lens substrate.

Optionally, the coating composition comprises at least one photochromic dye. Such a photochromic coating composition may comprise two or three photochromic dyes. The photochromic dye(s) can be combined so that, for example, by additive color mixing, any desired photochromic color can be produced. Typically, the at least one photochromic dye is selected from the group consisting of naphthopyrans, spironaphthopyrans, oxazines, spironaphthoxazines, benzopyrans, spirobenzoxzines, spirobenzopyrans, spiropyrans, chromenes, fulgides, fulgimides, spirooxazines, organo-metal dithiozonates, triarylmethanes, stilbenes, azastilbenes, nitrones, quinones, and mixtures thereof. For instance, the photochromic dye(s) are selected from the group consisting of:

Additionally or alternatively to the before exemplarily mentioned, the photochromic dye(s) can be selected from the group consisting of: CNN11, CNN12, CNN13, CNN14, CNN15, CNN16, CNN17 (K. K. Tokuyama, Tokyo, Japan), Reversacol Midnight Gray, Reversacol Pacific Blue, Reversacol Sunflower, Reversacol Corn Yellow (James Robinson, Ltd., Huddersfield, England), and mixtures thereof.

Typically, the photochromic dye(s) is/are present in an amount in a range of from 0.001 to 0.5% by weight, typically from 0.01 to 0.1% by weight, based on the total weight of the photochromic coating composition. The before mentioned ranges shall apply irrespective if only one single photochromic dye is comprised in the photochromic coating composition or if a mixture of different photochromic dyes are comprised in the photochromic coating composition.

The coated lens comprises a lens substrate, the lens substrate at least having a front surface and a back surface. The lens substrate comprises on at least one surface thereof a coating composition, the coating composition being described before. The lens substrate comprises on the front surface and/or on the back surface the coating composition. The coating composition on the front surface of the lens substrate comprises a surface facing away from the front surface of the lens substrate, at least the surface comprises a stamping. The coating composition on the back surface of the lens substrate comprises a surface facing away from the back surface of the lens substrate, at least the surface comprises a stamping. Typically, only the coating composition on the front surface of the lens substrate comprises a surface facing away from the front surface and at least the surface comprises a stamping.

For a coated lens comprising a lens substrate, the lens substrate at least having a front surface and a back surface, at least one of the front surface and the back surface being coated with a coating composition, the coating composition described before,

For the coated lens, the outermost surface comprises a stamping. In case, an additional coating or an additional coating composition is applied to the outermost surface, the additional coating or the additional coating composition again each comprises an outermost surface, i.e., a surface not being in contact with the outermost surface comprising the stamping, the outermost surface of the additional coating or the additional coating composition then is the outermost surface of the coated lens. The outermost surface of the additional coating or the additional coating composition may

The front surface is according to ISO 13666:2019(E), section 3.2.13, the surface of the lens intended to be fitted away from the eye. In the context of the present disclosure, the front surface of the lens substrate is defined analogously, the front surface of the lens substrate is the surface of the lens substrate intended to be fitted away from the eye. The back surface is according to ISO 13666:2019(E), section 3.2.14, the surface of the lens intended to be fitted nearer to the eye. In the context of the present disclosure, the back surface of the lens substrate is defined analogously, the back surface of the lens substrate is the surface of the lens substrate intended to be fitted nearer to the eye.

In the context of the present disclosure, a stamping shall mean at least one of the following:

The protrusion or the recess each typically has an equivalent tangential radius within a range of from 10 mm to 300 mm, further typically from 30 mm to 250 mm, more typically from 50 mm to 200 mm and most typically from 70 mm to 180 mm.

The equivalent tangential radius is measured by a white light interferometer, typically a Bruker ContourGT-X in VXI measurement mode with the deduction of the surface curvature of the lens substrate.

The protrusion typically provides to a coating comprising the protrusion an additional power. The protrusion further typically provides in a domain of the protrusion an additional power to a front surface and/or a back surface of a coated lens comprising the protrusion with respect to the respective front surface or with respect to the respective back surface of the coated lens outside the domain of the protrusion. The domain of a stamping formed as protrusion is defined below. The additional power typically is selected from at least one the following ranges:

The recess typically provides to a front surface and/or back surface of a coated lens comprising one coating or more coatings comprising the recess in a domain of the recess a difference in surface power with respect to a surface power of the respective front surface and/or the respective back surface outside the domain of the recess. The domain of a stamping formed as recess is defined below. The surface power is as defined in ISO 13666:2019(E), section 3.10.4 (surface power). The difference in surface power typically is selected from at least one the following ranges:

The protrusion typically causes a difference in focal length with respect to a surface comprising the protrusion. The recess typically causes a difference in focal length with respect to a surface comprising the recess.

Typically, a stamping formed as protrusion or formed as recess causes in a domain of the stamping, i.e., in a domain of the protrusion or in a domain of the recess, a difference in surface power with respect to a surface power of a front surface of a coated lens comprising the stamping but outside the domain of the stamping and/or a difference in surface power with respect to a surface power of a back surface of a coated lens comprising the stamping outside the domain of the stamping.

Typically, a stamping provides in a domain of the stamping a surface power to a lens surface of a coated lens which is different from a surface power of a lens surface, i.e., a front surface and/or a back surface, of the coated lens comprising a coating with the stamping but outside the domain of the stamping. Typically, a difference in surface power is within at least one range selected from the following group of ranges:

Typically, in case a stamping is forming one protrusion of a coated lens, the one protrusion comprises a surface topography selected from at least one of the following surfaces or pieced together from parts selected from at least one of the following surfaces:

In case a stamping is forming more protrusions of a coated lens, each of the more protrusions typically comprises a surface topography selected from at least one surface or pieced together from parts of at least one surface mentioned before. Each of the more protrusions may comprise a surface topography selected from at least one of a same surface, may be pieced together from parts of a same surface, may comprise a different surface or may be pieced together from parts of different surfaces.

In case a stamping is forming one recess of one coating or more coatings of a coated lens, the one recess typically is assumed to comprise a surface topography of a respective front surface and/or a respective back surface of a lens substrate to which the coating(s) is/are added to. In case a stamping is forming more recesses of one coating or more coatings of a coated lens, each of the more recesses are assumed to comprise a surface topography of a respective front surface and/or a respective back surface of a lens substrate to which the coating(s) is/are added to.

The stamping of a coated lens typically comprises:

The stamping of the coated lens comprising the domain on the front surface and/or on the back surface typically is formed as a protrusion, typically as one protrusion or as more protrusions, which is/are part of one coating or more coatings added to a respective front surface and/or a respective back surface of a lens substrate, i.e., the stamping is elevated with respect to the one or more coating(s).

The stamping of the coated lens comprising the domain of the front surface and/or of the back surface typically is formed as a recess, typically as one recess or as more recesses, which is/are part of one coating or more coatings added to a respective front surface and/or respective back surface of a lens substrate, the one recess or the more recesses typically being caused by the one coating or the more coatings, i.e., the one or more coating(s) is/are elevated with respect to the stamping.

Typically, the stamping comprises a domain which is smaller than a respective front surface and/or a respective back surface of a coated lens comprising the stamping.